WHERE  DID  LIFE  BEGIN? 


G.HILTON  SCRIBNER 


SCIENCES 
LIBRARY 


WILLIAM   DILLER   MATTHEW 


GIFT  OF 

WILLIAM  DILLER  MATTHEW 


EARTH 

SCIENCEf 
LIBRARY 


a 


WHERE  Dm  LIFE  BEGIN? 


A  BRIEF  ENQUIRY  AS  TO  THE  PROBABLE  PLACE  OF 

BEGINNING  AND  THE  NATURAL  COURSES  OF 

MIGRATION  THEREFROM  OF  THE  FLORA 

AND  FAUNA  OF  THE  EARTH 


BY 

G.    HILTON    SCRIBNER 


Let  the  great  world  spin  forever  down  the  ringing  grooves  of  change  " 

— LOCKSLEY  HALL 


NEW   YORK 

CHARLES   SCRIBNER'S   SONS 
1883 


COPYRIGHT  BY 
G.  HILTON  SCRIBNER 

1883 


TROWS 

PRINTING  AND   BOOKBINDING  COMPANY 
NEW   YORK. 


TO   MY   LIFE-LONG   FRIEND, 

THE  HONORABLE  CHAUNCEY  M.  DEPEW, 

WITH  WHOM,    IN   ALL  THE  DEPARTMENTS   OF    THOUGHT,    I     HAVE 
SPENT     SO    MANY    AND   SUCH    PLEASANT    HOURS,     THESE 
FEW     PAGES     ARE,    WITH     SINCERE     FRIENDSHIP 
AND  EARNEST    GOOD-WILL,    RESPECT- 
FULLY    DEDICATED    BY 
THE  AUTHOR. 


730243 


PREFACE. 


L/  HE  pressing  duties  of  an  ordinarily 
busy  life,  it  might  be  supposed,  would 
be  quite  sufficient  to  keep  one  not  specially 
trained  to  scientific  work  from  meddling 
with  such  matters  as  are  presented  in  this 
brief  monograph.  Indeed,  I  have  no  good 
excuse  for  finding  myself  engaged  in  this 
business.  It  might,  however,  be  said  in  ex- 
tenuation that  the  topics  I  have  been  deal- 
ing with  in  these  pages  have  occupied  my 
attention  from  time  to  time,  and  the  con- 
clusions have  been  lightly  held  by  me  as  mere 
probabilities  for  a  long  period.  With  later 
investigations  and  discoveries  they  began  to 
crystallize  into  opinions,  and  have  at  length 
assumed  the  firmness  of  convictions.  Having 
in  an  unguarded  hour  disclosed  them  to  a 
party  of  friends  well  fitted  to  judge  of  their 


vi  Preface. 

possible  correctness,  I  have  by  their    impor 
tunities  allowed  myself  to    be   betrayed  into 
print. 

It  has  been  my  earnest  desire,  however, 
in  writing  these  pages,  to  be  as  brief,  con- 
cise,  and  straightforward  as  possible  in  all 
statements  of  fact,  even  where  a  little  more 
elaboration  might  have  made  a  more  favorable 
impression.  I  have  also  striven  to  put  forth 
my  views  in  a  plain  garb,  and  I  shall  be 
abundantly  satisfied  if  I  have  made  myself 
understood  /  more  than  repaid  if  the  few  and 
crude  suggestions  I  have  gathered  shall  incite 
abler  and  better  equipped  men  to  enter  this 
very  interesting  field  of  inquiry,  and  bring 
forth  sucji  good  results  as  I  am  sure  await 
the  careful  and  conscientious  investigator  / 
and  only  regretful  if  I  have  used  unwit- 
tingly any  error  for  fact,  or  drawn,  in  the 
course  of  the  argument,  any  false  or  unwar- 
ranted conclusions. 

"  INGLEHURST,"  YONKERS,  Nov.  10,  1883. 


WHERE   DID   LIFE   BEGIN? 


WHERE  DID  LIFE*  BEGIN?  ,;';.•" 


THE  subject  of  the  distribution  of  plants 
and  animals  has  for  a  long  time  en- 
gaged the  attention  of  many  able,  persist- 
ent, and  discriminating  investigators.  Much 
time  and  effort  have  been  expended  in  simply 
observing  and  describing  the  various  means 
by  which  they  get  about  from  place  to  place. 
The  methods  and  means  by  which  the  seeds 
of  plants  are  carried  and  deposited  in  new 
localities,  the  agency  of  insects,  birds,  and 
other  animals  in  their  distribution,  no  less 
than  their  own  ingenious  contrivances  for 
floating  with  the  wind  and  tide,  and  for  catch- 
ing on  to  every  moving  object,  all  have  been 
carefully  observed  and  faithfully  chronicled. 

The  first  important  truth  enforced  by  these 
observations   is   that  all  organic  life  on    the 
earth  is  in  a  generic,  or  tribal  sense  at  least, 
i 


2  Where  did  Life  Begin  ? 

migratory  and  nomadic.  The  individuals  may 
be  rooted  and  stationary,  but  the  tribe  is  trav- 
elling, constantly  leaving  old  fields  and  sur- 
roundings and  as  constantly  arriving  in  new 
ones,  sometimes  crowded  out,  sometimes 
starved  out,  and  sometimes  invited  out,  but 
always  moving.  Moving  on  to  a  new  envi- 
ronment, better  suited,  taking  all  things  into 
consideration,  to  satisfy  the  pressing  needs  of, 
and  to  develop  and  raise  in  the  scale  of  being, 
both  the  individual  and  the  species. 

A  second  great  truth  taught  by  examining 
the  methods  of  these  movements  and  study- 
ing the  causes  of  this  ceaseless  tramp  of  or- 
ganic life  is,  that  certain  essential  elements  of 
the  environment  itself  are  usually  found  to  be 
travelling  with  or  a  little  in  advance  of  the 
migratory  species.  In  other  words,  the  rainfall 
and  isothermal  lines,  the  climatic  and  other 
conditions  of  life,  are  constantly  and  slowly 
changing  relative  to  the  locality,  but  moving 
in  fact.  It  has  been  frequently  observed  that 
certain  species,  occupying  some  particular  ter- 
ritory now,  have  at  some  recent  time  in  the 
past  been  enabled  by  such  changes  to  crowd 


Where  did  Life  Begin?  3 

out  other  occupants  of  the  same  territory,  and 
in  turn  will  be  undoubtedly,  by  similar  changes 
and  means,  crowded  out  themselves.  All 
kinds  of  plants  and  animals  which  have  re- 
mained in  one  locality  until  they  have  lost  the 
means  of  movement,  which  cannot  or  will  not 
travel,  must  sooner  or  later  first  degenerate 
and  then  be  exterminated.  For  instance,  a 
rain-belt  or  an  area  of  dew-fall  veers  slowly 
but  permanently  from  the  north  to  the  south ; 
an  arid  soil  is  made  fertile,  and  a  fertile  soil 
is  left  arid ;  the  grass  and  flowering  plants  in 
endless  variety  move  with  the  dew  or  the 
rain-belt ;  the  deer  follow  the  grass,  and  the 
wolves  follow  the  deer;  a  thousand  varieties 
of  insects  follow  the  flowering  plants,  and  the 
insectivorous  birds  and  other  animals,  herbiv- 
orous and  carnivorous,  bring  up  the  rear,  and 
so  on  through  all  the  interdependencies  of 
life,  the  change  of  a  single  essential  condi- 
tion, the  movement  of  one  variety,  causes  a 
disturbance  and  movement  of  all  in  the  neigh- 
borhood. Thence  comes  all  this  ceaseless  and 
migratory  activity  among  the  flora  and  fauna 
of  the  earth. 


4  Where  did  Life  Begin? 

This  condition  of  things  would  indicate  the 
possibility  at  least  that  life  upon  the  earth  had 
in  the  main  commenced  in  some  favored  area, 
and  travelled  thence  far  and  wide  over  the 
surface  of  the  globe,  driven  out  by  changes  of 
environment,  lessening  in  effect  the  favorable 
conditions  of  its  development  in  the  place  of 
its  beginning,  and  ever  beckoned  on  by  more 
favorable  conditions  in  adjacent  districts.  As 
there  are  no  plants  and  no  animals,  with  the 
exception  of  man,  and  possibly  his  compan- 
ion the  dog,  and  his  pest  the  rat,  that  can 
thrive  in  most  latitudes  where  any  life  is  pos- 
sible, so  it  is  very  evident  that  plants  and 
animals,  as  we  now  see  them,  could  not  have 
made  their  advent  upon  the  earth  universally 
or  simultaneously.  Every  geological  fact  con- 
tradicts both  suppositions.  Besides,  to  allege 
either  is  to  claim,  first,  that  all  parts  of  the 
earth  became  habitable,  for  some  form  of  life, 
at  the  same  time,  which  is  scarcely  possible ; 
and,  secondly,  such  an  allegation  would  do 
away  with  the  main  question  of  distribution, 
render  superfluous  most  means  of  movement, 
and  make  it  sheer  nonsense  to  talk  about  the 


Where  did  Life  Begin?  5 

time,  methods,  and  character  of  the  distribu- 
tion of  that  which  had  from  the  beginning  been 
fully  distributed.  It  is  much  more  probable 
that  life  made  its  first  advent  upon  this  globe 
in  some  favored  locality,  and  not  everywhere 
at  once. 

It  would  seem  as  axiomatic  a  proposition 
as  can  be  made  in  natural  science,  that  life 
would  make  its  first  appearance  on  that  part 
of  the  earth,  or  on  that  part  of  any  developing 
planet,  which  by  climatic  and  all  other  con- 
current conditions  was  first  prepared,  if  not  to 
originate  at  least  to  receive  and  maintain  it. 
Nothing  can  be  more  certain  than  that  it  could 
not  make  its  first  appearance  on  that  part,  or 
on  any  of  those  parts,  wanting  these  condi- 
tions. 

By  concurrent  conditions  of  climate  or  tem- 
perature, wherever  the  phrase  is  used  herein, 
I  mean  such  currents  of  air  and  ocean,  such 
evaporation  and  condensation  of  water,  such 
disintegration  of  rock,  such  electrical  and 
chemical  changes,  new  combinations,  phenom- 
ena, and  movements  as  are  influenced  by  or 
accompany  changing  climate  or  temperature, 


6  Where  did  Life  Begin? 

together  with  all  the  secondary  and  remote 
effects  caused  thereby.  And  in  speaking  of 
the  first  appearance  of  life  it  matters  not,  to 
my  mind,  whether  it  was  a  creation,  a  develop- 
ment, or  a  transplantation ;  whether  it  was  a 
lichen  on  the  rock  or  a  monad  in  the  sea ;  a 
single  solitary  primordial  cell,  or  one  molecule 
of  plasmic  matter  anywhere.  This  inquiry  is 
not  for  the  causes,  methods,  character,  or 
extent  of  first  life ;  it  is  simply  and  only  con- 
cerning its  probable  primus  locus. 

If  we  are  so  fortunate  as  to  discover  where 
life  began  on  the  earth,  it  will  be  safe  enough 
to  rest  upon  the  assumption  that  much,  if  not 
all,  of  the  present  life  on  the  globe  is  its  le- 
gitimate result  and  outcome. 


I. 


ARE  there,  then,  any  data,  any  accepted  facts 
touching  the  condition  of  our  globe  antece- 
dent to  the  advent  of  plants  and  animals 
which  would  enable  us  to  compare  and  con- 
trast its  past  with  its  present  condition,  and 


Where  did  Life  Begin?  7 

which  under  known  laws  would  indicate  what 
portion  of  the  earth's  surface  first  became,  by 
temperature,  climate,  and  other  concurrent 
conditions,  habitable  for  life  ?  Can  any  rea- 
sonable, probable,  and  still  existing  cause  be 
discovered  occurring  in  the  very  centre  of 
such  first  habitable  portion  which  would  have 
dispersed  all  vegetal  and  animal  life  and 
sent  it  in  equal  distribution  through  all  the 
seas  and  over  all  the  great  continents  as  rap- 
idly as  such  other  portions  of  the  earth  be- 
came by  temperature,  climate,  and  other  con- 
ditions ready  to  receive  and  maintain  it  ?  Is 
there  any  one  locality  answering  to  these 
conditions,  and  yet  of  which  it  may  be  said, 
in  a  grander  and  truer  sense  than  it  was  said 
of  Rome,  that  all  roads  lead  to  and  from  it ; 
not  only  highways  diverging  to  every  part 
of  the  world,  but  with  vehicles  upon  them  ; 
seed-wagons  running  constantly  in  the  direc- 
tion of  the  most  favorable  distribution  and  to 
the  remotest  parts  of  the  earth  ?  Any  local- 
ity so  related  to  the  topography  of  the  whole 
earth  as  to  render  such  extensive  movements 
of  plants  and  animals  from  it  in  all  conceiva- 


8  Where  did  Life  Begin  ? 

ble  directions,  and  to  all  distances,  not  only 
easy  and  probable,  but  consistent  with  their 
present  distribution  ?  Is  there  anything  in  sim- 
ilarity of  form,  anatomy,  structure,  size,  color, 
food,  habits,  habitat,  longevity,  modes  of 
propagation,  terms  of  gestation,  and  capacity 
for  inter-breeding  between  certain  flora  and 
fauna  of  the  Eastern  continents  and  the  West- 
ern, which  would  suggest  that  many  species 
and  varieties  so  widely  separated  might  have 
come  originally  from  the  same  locality  and 
ancestry?  Are  plants  and  animals  always 
improved,  developed,  and  rendered  prolific 
more  by  being  moved  one  way  than  another  ? 
Are  the  prevailing  bottom  currents  of  air  and 
ocean  in  the  direction  of  such  favorable  move- 
ments ?  Are  cases  of  extermination  and  de- 
generation the  result  of  a  counter-movement, 
or  a  failure  to  make  such  favorable  move- 
ments ? 

Many  facts  and  considerations  exist  and 
may  be  presented  pointing  to  a  solution  of 
these  questions,  and  fairly  answering  some 
of  them. 

Let   us    consider,   in   the   first   place,    the 


Where  did  Life  Begin?  9 

probable  condition  of  the  earth  previous  to 
the  advent  of  any  sort  of  life  upon  its  sur- 
face. A  large  portion  of  those  who  have 
formed  any  intelligent  opinions,  in  the  light 
of  modern  thought  and  investigation,  upon 
the  subject  of  cosmogony,  believe  and  hold 
very  firmly  that  the  earth  was  at  one  time  an 
intensely  hot  globe — indeed  a  molten  mass, 
and  that  in  the  lapse  of  time  it  has  cooled 
down  by  radiation  to  its  present  temperature. 
It  is  not  at  all  necessary  for  the  purposes  of 
the  present  inquiry  to  examine  the  so-called 
nebular  theory,  nor  even  to  ask  when  or  how 
this  globe  became  so  heated,  nor  to  what 
extent  it  has  now  become  cooled,  nor  need 
we  inquire  whether  the  earth  is  now  but  a 
molten  mass  covered  with  a  comparatively 
thin  crust,  or  has  cooled  and  hardened  to  its 
very  centre.  It  is  important,  however,  to 
have  it  understood  at  the  outset  that  the 
facts  and  considerations  here  presented  are 
addressed  to  those,  and  those  only,  who  have 
reached  and  adopted  the  conclusion  that  this 
globe,  at  some  time  in  the  process  of  its  for- 
mation and  development,  passed  through  a 


io  Where  did  Life  Begin? 

fiery  ordeal,  that  the  primary  rocks  are  of  ig- 
neous formation,  and  that  there  are  many 
other  existing  conditions  and  obvious  facts 
which  cannot  well  be  accounted  for  except 
upon  the  hypothesis  that  the  whole  earth  was 
once  a  molten  mass.. 

Even  after  these  admissions  one  embarrass- 
ment presents  itself,  happily,  however,  not 
affecting  the  argument,  viz. : 

So  fully  has  every  conceivable  inference, 
every  supposable  fact  and  phenomenon  in  the 
development  and  history  of  the  earth,  been 
reviewed  and  discussed  over  and  over  again, 
in  the  light  of  this  primitive  glowing  molten 
mass,  by  able  and  discriminating  writers,  that 
it  may  seem  presumptuous  at  this  late  day  to 
attempt  any  new  deduction,  or  to  draw  any 
new  conclusion  radically  important,  touching 
this  matter.  But  if  the  views  here  presented 
have  been  expressed  before,  in  the  relation 
of  cause  and  effect,  the  writer  has  not  been 
fortunate  enough  to  meet  with  them,  and  it 
is  quite  safe  to  say  that  if  they  are  correct 
their  significance  as  a  factor  in  other  problems 
at  least  will  not  be  questioned. 


Where  did  Life  Begin  ?  1 1 

It  is  not  claimed  that  these  views  have  been 
proved  to  be  true  inductively,  but  there  are 
certain  facts  and  phenomenon  pointing  di- 
rectly to  definite  conclusions  hereinafter  stated 
which  I  am  sure  every  one  holding  and  be- 
lieving that  the  earth  was  at  one  time  a 
molten  mass  will  find  it  easier  and  more  rea- 
sonable to  admit  than  deny. 

Regarding  the  earth,  then,  as  at  one  time  an 
intensely  hot  globe,  totally  destitute  of  organic 
life,  one  of  the  principal  and  indispensable  con- 
ditions of  rendering  it  habitable  for  plants  and 
animals  evidently  would  be  the  radiation  into 
space  of  its  excessive  and  destructive  heat. 
The  accomplishment  of  this,  with  the  train  of 
concurrent  effects  which  would  follow,  or  at 
least  ever  have  followed  the  gradual  reduction 
of  temperature,  is  all  that  would  be  necessary 
to  render  the  earth  a  suitable  place  for  the 
maintenance  of  vegetal  and  animal  life.  At 
any  rate  this  is  precisely  what  has  taken  place 
since  the  commencement  of  the  azoic  age, 
and  is  still  taking  place  on  parts  of  the  earth's 
surface  to-day,  visible  and  obvious  to  any 
observer. 


12  Where  did  Life  Begin? 

Our  inquiry,  therefore,  is  reduced  to  this 
question :  What  part  or  parts  of  the  earth's 
surface  first  became  sufficiently  cooled  by  ra- 
diation to  be  habitable  by  plants  and  animals  ? 

A  supposed  case  may  help  us  in  reaching 
a  correct  answer  to  this  question.  Let  us 
assume,  then,  that  the  earth,  at  the  time  it  was 
a  molten  mass,  had  been  and  was  revolving 
in  an  orbit  so  near  the  sun  that  the  amount 
of  heat  it  would  have  been  receiving  from  the 
sun  would  have  just  equalized  the  amount  of 
heat  it  was  losing  by  radiation.  Under  these 
conditions  it  would  have  cooled  as  the  sun 
cooled — neither  faster  nor  slower.  This  helps 
us  to  understand  that  the  heat  received  by 
the  earth  from  the  sun  is,  and  ever  has  been, 
an  offset,  so  far  as  it  goes,  to  the  heat  lost 
from  the  earth  by  radiation.  A  statement  of 
the  loss  of  heat  from  the  earth  during  any 
definite  time  may  be  formulated  in  this  way : 
From  the  heat  lost  by  the  earth  by  radiation 
during  a  given  period  subtract  the  heat  re- 
ceived by  the  earth  from  the  sun  during  the 
same  period,  and  the  remainder  will  be  the 
earth's  net  or  actual  loss  of  heat.  Sidereal 


Where  did  Life  Begin?  13 

heat  received  by  the  earth  being-  infinitesimal 
in  comparison,  is  not  here  taken  into  the  cal- 
culation. But  were  it  more  considerable,  it 
would  not  be  important  in  this  connection,  for 
it  falls  upon  all  parts  of  the  earth  about  equally. 

It  is  evident  from  the  present  condition  of 
the  earth's  surface,  that  at  the  time  it  was  a 
molten  mass,  and  for  a  long  time  thereafter,  it 
radiated  heat  into  space  much  more  rapidly 
than  it  received  heat  from  the  sun ;  but  never- 
theless the  heat  of  the  sun  is,  and  always  has 
been,  offsetting  the  loss  of  heat  from  the  earth 
by  radiation  to  the  full  extent  of  the  heat 
which  the  earth  had  been  receiving  from  the 
sun  during  the  time. 

But  this  sun-heat,  this  offset  to  radiation, 
has  not  been  received  by  all  parts  of  the  earth 
equally.  The  equatorial  belt,  or  torrid  zone, 
has  always  received  the  most  per  square  foot, 
or  in  proportion  to  its  area.  The  two  inter- 
mediate or  temperate  zones  have  received 
the  next  largest  amount  per  square  foot,  or  in 
proportion  to  their  area ;  while  the  polar  or 
frigid  zones  have  received  the  least  per 
square  foot,  or  in  proportion  to  their  area. 


14  Where  did  Life  Begin? 

If  the  amount  of  sun-heat  received  at  the 
equator  be  rated  at  1,000,  then,  upon  the  same 
basis,  the  average  of  sun-heat  throughout 
the  torrid  zone  should  be  rated  at  975,  the 
average  sun-heat  throughout  the  temperate 
zones  at  757,  and  the  average  sun-heat 
throughout  the  frigid  zones  at  454,  or  less 
than  one-half  that  of  the  torrid  and  less  than 
two-thirds  that  of  the  temperate  zones.  We 
speak  here,  and  shall  hereafter,  of  the  geo- 
graphical zones  of  the  earth  for  the  sake  of 
convenience. 

The  greatest  amount  of  heat  received  from 
the  sun  and  offsetting  radiation  from  the  earth, 
other  things  being  equal,  is,  of  course,  as  we 
have  seen,  at  the  equator,  and  less  and  less 
every  degree  north  and  south  of  this  line  to 
the  poles.  If,  then,  the  frigid  zones  have 
been  during  all  this  time  receiving  the  least 
heat  from  the  sun — the  least  offset  to  their 
own  loss  of  heat  by  radiation — does  it  not 
follow  that  they  were  the  first  parts  of  the 
earth  sufficiently  cooled  to  maintain  vegetal 
and  animal  life  ? 

The  inference  seems  inevitable. 


Where  did  Life  Begin?  15 


II. 


BUT  there  are  other  facts  leading  to  the 
same  conclusion  quite  as  suggestive  in  their 
way  as  those  which  have  been  cited.  As 
every  one  knows,  the  earth  is  flattened  at  the 
poles  and  bulged  at  the  equator,  as  it  should 
be  if  it  was  once  a  revolving  liquid  globe. 
This  gives  to  the  polar  sides  an  increased 
area  of  radiating  surface,  and  to  this  extent 
an  increased  loss  of  heat.  Thus  it  is  evi- 
dent that  the  earth  is,  and  always  has  been, 
radiating  more  heat  into  space  polewise  than 
any  other  one  way,  and  this  to  a  limited  extent 
has  kept  the  polar  regions  in  advance  of  the 
equatorial  in  the  process  of  cooling. 

Another  effect  of  the  same  cause  and  bear- 
ing in  the  same  direction  is  this  :  The  equato- 
rial diameter  of  the  earth  is  about  twenty-six 
miles  longer  than  its  diameter  polewise.  This 
condition  also  favors  the  advanced  cooling  of 
the  polar  regions.  First,  the  earth  is  so  much 
thinner  polewise  than  equatorially,  and  conse- 
quently there  is  less  mass  per  square  foot  to 


1 6  Where  did  Life  Begin? 

be  cooled  by  polewise  radiation  than  by 
equatorial ;  or,  secondly,  this  difference  of  di- 
ameters is  equivalent  to  having  had  a  layer 
around  the  earth  of  molten  matter  to  be  cooled 
thirteen  miles  in  thickness  at  the  equator,  and 
tapering  off  to  nothing  somewhere  north  of  the 
Tropic  of  Cancer  and  south  of  the  Tropic  of 
Capricorn  in  excess  of  the  molten  matter  to  be 
cooled  by  polewise  radiation,  and  this  would 
have  tended  to  keep  the  polar  regions  con- 
stantly in  advance  of  all  other  parts  of  the 
earth  in  cooling. 

In  addition  to  all  this,  it  is  obvious  that  the 
shape  given  to  the  earth  by  this  difference  of 
diameters — this  flattening  at  the  poles  of  itself 
—would  somewhat  lessen  the  angles  of  inci- 
dent and  reflection  of  the  sun's  rays  within  the 
polar  regions,  which  would  still  more  decrease 
their  effect,  and  so  reduce  the  offset  to  loss  of 
heat  by  radiation  within  these  polar  regions. 

Can  it  then  be  doubted  that  the  frigid  zones 
first  became  cool  enough  to  maintain  life  as 
we  now  see  it  on  the  earth  ? 

To  state  the  matter  briefly,  the  polar  regions 
have  received  less  heat  from  the  sun,  have  had 


Where  did  Life  Begin?  17 

less  matter  to  cool,  and  have  radiated  heat 
into  space  more  rapidly  in  proportion  to  mass 
than  the  equatorial  belt  or  any  other  parts  of 
the  earth's  surface.  In  the  light  of  these  facts 
it  seems  to  me  the  following  conclusions  can- 
not be  well  avoided : 

First. — That  the  polar  zones  having  led  the 
advance  in  cooling,  have  had  in  turn  all  the 
temperatures,  climates,  and  climatic  conditions 
which  at  any  time  the  torrid  and  temperate 
zones  have  had,  in  addition  to  long  later 
periods  of  cooler  temperature  and  climates 
than  either. 

Second. — Therefore,  that  at  one  epoch  or 
another  the  polar  regions  of  the  earth  have 
enjoyed  all  the  various  temperatures  and  cli- 
matic conditions  necessary  to  maintain  all  the 
well  nigh  infinite  forms  of  life,  both  vegetal  and 
animal,  which  are  now,  or  ever  have  been, 
upon  this  globe.  At  the  risk  of  being  tedious 
let  us  state  this  hypothesis  in  another  way. 

The  whole  globe  was  once  a  molten  mass 
too  hot  to  maintain  life.  The  polar  regions 
were  then  too  hot  for  that  purpose.  These 
same  regions  are  now  too  cold  to  maintain 


1 8  Where  did  Life  Begin? 

such  life  as  we  find  on  other  parts  of  the  earth. 
Nothing,  then,  can  be  more  obvious  than  that 
the  temperature  of  these  now  frigid  zones,  in 
sliding  gradually  from  the  first  extreme  of  heat 
to  the  last  extreme  of  cold,  must  have  passed 
slowly  through  all  the  grades  of  temperature 
and  climatic  conditions  which  were  exactly 
suited  at  one  time  or  another  to  all  the  varie- 
ties of  plants  and  animals  which  now  live,  or 
ever  have  lived  on  the  earth. 

There  is  no  escape  from  this  conclusion,  ex- 
cept by  asserting  that  the  usual  climatic  and 
concurrent  conditions  did  not  in  this  case  fol- 
low along  the  line  of  lowering  temperature. 
But  this  is  not  only  raising  a  groundless  objec- 
tion, one  without  a  single  fact  to  support  it, 
but  it  is  also  one  which  disturbs,  contradicts, 
and  reverses  the  usual  order  of  things.  Cer- 
tainly the  onus  probandi  should  rest  on  him 
who  invokes  the  supposition. 

Of  course  the  usual  number  in  considering 
this  question  will  very  properly  ask  whether 
there  was  time  enough  for  organic  develop- 
ment after  the  polar  zones  were  cool  enough 
to  maintain  life,  and  before  the  other  parts 


Where  did  Life  Begin?  19 

of  the  earth  had  reached  the  same  tempera- 
ture and  climatic  conditions.  Well,  time  is 
the  infinite  factor  in  every  calculation  of  this 
sort;  nature,  reason,  and  observation  unite 
in  saying  "  it  is  illimitable  and  all-sufficient." 
Certainly  there  has  been  and  will  be  time 
enough  for  everything. 

If  the  first  isothermal  belt,  including  the 
highest  heat  degrees  in  which  any  life  is  pos- 
sible had  swept  southward  at  the  rate  of  one 
English  mile  in  a  millennium,  it  would  have 
taken  about  6,000,000  years  for  it  to  have 
travelled  from  the  north  pole  to  the  equator. 
This  would  seem  a  sufficient  lapse  of  time  for 
a  great  advance  and  development  of  all  forms 
of  life  moving  within  the  zone.  I  am  well 
aware  that  eminent  geologists  are  assuming 
much  longer  periods  for  the  life-history ;  for 
instance  Professor  Dana  mentions  48,000,000 
years  as  an  estimated  minimum  of  time  since 
the  commencement  of  the  Silurian  age  ;  while 
Sir  William  Thomson  estimates  geological 
time  at  100,000,000  years,  Haughton  at  twice 
that  period,  and  many  others  at  thousands 
of  millions.  Now,  without  courting  an  ear- 


2O  Where  did  Life  Begin  ? 

nest  approval  for  these,  or  any  estimates  for 
that  matter,  of  the  lapse  of  time  since  life 
•began — the  data  being  so  insufficient  and  the 
conclusions  so  widely  different — yet  it  is  emi- 
nently conservative,  in  view  of  them  and  other 
accepted  calculations,  to  claim,  so  far  as  time  is 
a  factor,  that  a  first  life-bearing  climate  might 
have  commenced  anywhere  and  travelled  ev- 
erywhere (and  all  sorts  of  organisms  might 
have  travelled  with  it  in  the  natural  thorough- 
fares) over  a  globe  only  25,000  miles  in  cir- 
cumference without  moving  faster  than  one 
mile  in  ten  millenniums. 

On  the  other  hand,  a  zone  of  torrid  climate 
beginning  near  and  surrounding  the  north 
pole,  and  creeping  thence  to  the  equator  at 
such  a  slow  pace,  would  have  given  ample 
time  in  its  long  journey  for  the  development 
of  highly  complex  forms  evolved  from  the  very 
simplest,  for  all  organisms  moving  within  its 
isothermal  limits. 

Considerations  will  be  hereafter  presented 
showing  absolutely  that  there  was  time  enough 
and  to  spare  for  vast  and  highly  developed 
orders  of  life  within  the  frigid  and  temperate 


Where  did  Life  Begin?  21 

zones  before  any  movement,  and  probably  be- 
fore the  equatorial  belt  was  cool  enough  to 
maintain  life,  certainly  before  the  first  torrid 
climates  near  the  poles  became  cold  enough 
to  exclude  it.  We  may  therefore  safely  con- 
clude, if  the  code  of  natural  laws  has  been  uni- 
formly in  force — 

First. — That  life  commenced  on  those  parts 
of  the  earth  which  were  first  prepared  to 
maintain  it;  at  any  rate,  that  it  never  could 
have  commenced  elsewhere. 

Second. — As  the  whole  earth  was  at  one 
time  too  hot  to  maintain  life,  so  those  parts 
were  probably  first  prepared  to  maintain  it 
which  cooled  first. 

Third. — That  those  parts  which  received 
the  least  heat  from  the  sun,  and  which  radiat- 
ed heat  most  rapidly  into  space,  in  proportion 
to  mass,  and  had  the  thinnest  mass  to  cool, 
cooled  first. 

Fourth. — That  those  parts  of  the  earth's 
surface,  and  those  only,  answering  to  these 
conditions,  are  the  arctic  and  antarctic  zones. 

Fifth. — That  as  these  zones  were  at  one 
time  too  hot,  and  certain  parts  thereof  are 


22  Where  did  Life  Begin? 

now  too  cold,  for  such  life  as  inhabits  the 
warmer  parts  of  the  earth,  these  now  colder 
parts,  in  passing  from  the  extreme  of  heat  to 
the  extreme  of  cold,  must  have  passed  slowly 
through  temperatures  exactly  suited  to  all 
plants  and  all  animals  in  severalty  which  now 
live  or  ever  lived  on  the  earth. 

Sixth. — If  the  concurrent  conditions  which 
have  usually  followed  lowering  temperature 
followed  the  climatic  changes  in  this  case,  life 
did  commence  on  the  earth  within  one  or  both 
of  certain  zones  surrounding  the  poles,  and 
sufficiently  removed  therefrom  to  receive  the 
least  amount  of  sunlight  necessary  for  vege- 
tal and  animal  life. 

It  seems  almost  superfluous  to  say  that 
those  parts  of  the  earth  which  first  became 
cool  enough  to  maintain  life  had  a  climate 
warmer  at  that  time  than  that  which  we  now 
call  torrid.  It  was  for  an  epoch,  and  probably 
a  very  long  one,  as  hot  as  it  could  be  and 
maintain  life. 

It  is  also  quite  obvious,  in  the  light  of  the 
foregoing  considerations,  that  as  the  temperate 
zones  have  always  received  more  heat  from  the 


Where  did  Life  Begin?  23 

sun,  and  have  had  more  mass  per  square  foot 
to  cool,  in  proportion  to  radiating  surface,  than 
the  polar  zones,  so,  on  the  other  hand,  they 
have  always  received  less  heat  from  the  sun 
and  have  had  less  mass  to  cool,  in  proportion 
to  radiating  surface,  than  the  torrid  zone  ;  and 
so  when  the  arctic  zones  cooled  from  a  tropi- 
cal to  what  we  now  call  a  temperate  climate, 
the  temperate  zones  had  cooled  down  to  that 
temperature  which  we  now  call  a  torrid  cli- 
mate, while  the  equatorial  belt  was  still  too 
hot  for  any  form  of  life.  Thus  the  lowering 
of  temperature,  climatic  change,  and  that  life 
which  made  its  advent  in  these  zones  surround- 
ing the  poles,  have  crept  thence  slowly  along, 
pari  passu,  from  these  polar  regions  to  the 
equator.  Doubtless,  through  all  geologic 
time,  wave  after  wave  of  climatic  change  and 
corresponding  forms  of  life,  including  the  re- 
motest extinct  species,  from  laurentian  to  allu- 
vium, from  eozoon  to  mammal,  whose  several 
biographies  in  the  rocks,  are  now  called 
epochs,  have  followed  each  other  in  succes- 
sion from  this  originally  prolific  polar  zone  to 
the  equatorial  belt. 


24  Where  did  Life  Begin  f 


III. 


LET  us  now  pass  to  a  consideration  of  the 
present  condition  of  the  earth  and  the  life 
upon  it,  and  see  how  far  things  as  we  find 
them  tally  with  the  conclusions  we  have  now 
reached.  Before  doing  so,  however,  one  or 
two  preliminary  suggestions  may  be  advisable. 
There  is  a  very  interesting,  and  at  least 
plausible,  theory  gaining  ground,  that  from  the 
eccentricity  of  the  earth's  orbit,  and  other 
causes  too  numerous  to  state  here,  the  north- 
ern and  southern  hemispheres  are  alternately 
submerged  and  drained  off  as  the  vast  ice 
accumulations  first  around  one  pole  and  then 
around  the  other  change  slightly  the  centre 
of  gravity  of  the  earth  alternately  to  the  north 
and  the  south  of  the  plane  of  the  equator, 
and  that  each  hemisphere  makes  the  round 
of  these  changes  in  a  long  period  or  year, 
consisting  theoretically  of  about  26,000,  but 
practically,  owing  to  the  reverse  movement 
of  the  precession  of  the  equinoxes,  of  about 
22,500  of  our  common  years. 


Where  did  Life  Begin?  25 

Whether  this  is  so,  and  whether  at  the  time 
of  the  first  advent  of  life  upon  the  earth, 
southern  continents  now  submerged  were 
drained  off,  and  the  northern  continents  sub- 
merged, or  whether  the  northern  continents 
were  drained  off  and  the  southern  submerged, 
as  at  present,  is  quite  immaterial  for  the  pur- 
poses of  our  inquiry.  One  thing  is  certain, 
that  with  the  present  amount  of  water  upon 
the  earth,  to  submerge  the  continents  of  the 
northern  hemisphere  as  deep  as  the  floor  of  the 
southern  oceans,  would  necessarily  drain  off 
vast  bodies  of  land  in  the  southern  hemi- 
sphere, and  give  the  south  pole  a  surrounding 
zone  of  land  such  as  the  north  pole  now  has. 
Such  a  condition  of  things  would  keep  all  life 
in  a  constant  migration,  north  and  south,  and 
almost  from  pole  to  pole — at  any  rate,  from 
one  frigid  zone  to  the  other. 

Since  then  it  makes  no  difference,  for  the 
purposes  of  our  inquiry,  whether  there  have 
been  such  alternate  changes,  and  also  to  avoid 
distracting  the  attention  by  looking  first  to 
one  pole  and  then  to  the  other,  we  will  con- 
sider this  matter  as  though  the  continents  and 


26  Where  did  Life  Begin? 

oceans  had  always  been  as  we  now  find  them, 
and  confine  our  attention  to  the  more  fully 
explored  arctic  regions,  rather  than  both  frigid 
zones. 

As  might  be  readily  supposed,  these  arctic 
regions  which  first  became  cool  enough  to 
maintain  life,  would  from  the  same  causes  be 
the  first  to  become  too  cold  for  the  same  pur- 
pose. And  this  cold  would  occur  first  as  a 
temperate  climate  near  and  around  the  pole ; 
at  any  rate,  in  the  centre  of  a  zone  just  suffi- 
ciently removed  from  the  pole  to  combine  the 
influence  of  the  sun  with  its  own  cooling  tem- 
perature, so  as  to  become  the  first  fit  habita- 
tion of  life. 

This  central  cold  creating  a  temperate  clim- 
ate would  thus  have  become  the  first  and  all- 
sufficient  cause  of  a  dispersion  and  distribu- 
tion of  both  the  tropical  plants  and  animals 
over  another  zone  next  south,  next  further 
removed  from  the  pole,  and  next  sufficiently 
cool  to  maintain  such  life.  Moreover,  this 
cooler  climate  occurring  in  the  centre  would 
have  driven  out  and  dispersed  such  life 
equally,  in  all  possible  directions.  So,  if  the 


Where  did  Life  Begin?  27 

first  habitable  zone  included  the  northernmost 
land  of  all  the  great  continents  which  con- 
verge around  the  north  pole,  this  dispersion 
from  an  increasing  cold  to  the  north  of  each 
of  them  would  have  sent  southward  plants 
and  animals  from  a  common  origin  and  ances- 
try, to  people  and  to  plant  all  the  continents 
of  the  earth,  with  the  possible  exception  of 
Australia,  whose  flora  and  fauna  are  certainly 
anomalous  and  possibly  indigenous. 

I  have  mentioned  cold  as  the  all-sufficient 
cause  of  a  dispersion  to  the  southward  of 
plants  and  animals.  To  those  who  would  ad- 
mit the  cause  but  doubt  the  effect,  I  would 
quote  a  sentence  from  the  admirable  book  of 
Professor  Dana,  entitled  "The  Geological 
Story  Briefly  Told,"  in  which  he  says  (speak- 
ing of  the  glacial  epoch,  page  224)  :  "  There 
must  have  been  some  exterminations  as  a  con- 
sequence of  the  cold  of  the  glacial  period  and 
of  the  ice  of  the  high  latitude  regions  ;  many 
plants  were  driven  south  by  the  coming  on  of 
the  cold,  and  thus  escaped  destriiction,  and 
some  of  these  now  live  on  Mount  Washing- 
ton and  other  high  summits  of  temperate  North 


28  Where  did  Life  Begin? 

America.  Birds  must  have  shortened  their 
northward  migrations  and  lengthened  them 
southward,  and  for  the  most  part  may  have 
escaped  catastrophe — the  beasts  of  prey,  cat- 
tle, and  other  large  mammals  of  Drift  latitudes 
must  also,  to  a  great  extent,  have  moved 
toward  the  tropics  as  the  rigors  of  the  ap- 
proaching ice  period  began  to  be  felt."  If  the 
comparatively  swift  coming  cold  of  the  glacial 
period  could  have  moved  to  the  southward, 
over  vast  areas,  all  the  plants  and  animals  of 
the  northern  hemisphere,  how  much  more  ade- 
quate and  effectual  for  the  same  purpose  must 
have  been  the  gradual  lowering  of  tempera- 
ture during  the  earlier  and  immensely  longer 
periods  of  the  earth's  life  history. 


IV. 


LET  us  now  see  how  admirably  the  earth  is 
adapted  by  its  surface  formation  and  topo- 
graphy, for  a  southern  migration  from  a  zone 
surrounding  the  north  pole.  In  the  first 
place,  nearly  the  whole  of  the  earth's  surface 


Where  did  Life  Begin  ?  29 

(and  all  the  northern  hemisphere)  is  cor- 
rugated north  and  south  with  alternate  con- 
tinents and  deep  sea-channels  almost  from 
pole  to  pole.  Both  the  eastern  and  western 
continents  extend  with  unbroken  land  con- 
nections from  the  arctic  zone  through  the 
northern  temperate,  the  torrid,  and  through 
the  southern  temperate,  almost  to  the  antarctic 
zone.  Between  these  great  continents  lie  the 
deep  oceans,  whose  channels  run  north  and 
south  through  as  many  degrees  of  latitude. 
The  great  air  and  ocean  currents  run  north 
or  south  ;  all  the  mountain  ranges  of  the  west- 
ern continent  and  many  of  the  eastern  contin- 
ents run  mainly  north  and  south.  Nearly  all 
the  great  rivers  of  the  northern  hemisphere 
run  north  or  south.  To  a  southern  migra- 
tion— in  other  words,  a  migration  from  the 
arctic  region  toward  the  equator — these  pe- 
culiarities of  topography,  these  great  corruga- 
tions and  mountain  ranges,  these  channels  and 
currents,  are  roads  and  vehicles,  guides  and 
helps  ;  while  to  an  east  and  west  migration  the 
same  features  are  not  only  obstacles  and  hin- 
drances, but  in  the  main  barriers  insuperable. 


30  Where  did  Life  Begin? 

The  impassability  of  mountain  ranges  for 
most  plants  is  shown  by  the  fact  that  strongly 
marked  varieties  in  great  numbers  and  many 
distinct  species  occur  upon  the  eastern  slopes 
of  the  Rocky  Mountains,  the  Sierra  Nevadas, 
the  Alleghanies,  and  even  lower  ranges,  which 
are  not  found  at  all  upon  their  western  sides, 
and  vice  versa.  Such  a  condition  of  things, 
incompatible  as  it  is  with  an  eastern  and 
western  migration,  is  quite  consistent,  how- 
ever, with  a  north  and  south  movement.  For 
all  the  climatic  conditions,  especially  that  of 
rain-fall,  are  so  different  on  the  opposite  sides 
of  all  long  mountain  ranges,  that  the  same 
variety  split  and  separated  by  the  northern 
extremities  of  these  ranges  would,  in  moving 
southward  along  their  eastern  and  western 
sides,  and  encountering  such  diverse  condi- 
tions, have  become  in  the  course  of  time,  under 
the  laws  of  adaptation,  distinct  varieties,  and 
probably  different  species. 

It  may  be  well  now  to  examine  some  of  the 
conditions  assisting  this  movement.  Hot  air 
being  lighter  than  cold,  the  heated  air  of  the 
northern  equatorial  belt  has  always  risen  and 


Where  did  Life  Begin?  31 

passed  mainly  toward  the  north  pole  in  an 
upper  current,  while  the  cooler  and  heavier 
currents  from  the  north  have  swept  south- 
ward hugging  the  surface  of  the  continents, 
laded  with  pollen,  minute  germs  and  spores, 
and  all  the  winged  seeds  of  plants,  bending 
grass  and  shrubs  and  trees  constantly  to  the 
southward,  and  so,  by  small  yearly  increments 
moving  the  whole  vegetal  kingdom  through 
valleys  and  along  the  sides  of  mountain  ranges, 
down  the  great  continents,  always  moving 
with,  and  never  across  these  great  surface 
corrugations.  It  is  unnecessary  to  add  that 
all  insects  and  herbivorous  animals  would 
follow  the  plants,  or  that  the  birds  and  car- 
nivorous animals  would  follow  the  herbivor- 
ous animals  and  the  insects.  So,  too,  the  cur- 
rents of  the  ocean  have  been  established  in 
obedience  to  similar  laws ;  as  hot  water  is 
lighter  than  cold,  great  surface  "currents  have 
been  formed  in  both  the  Atlantic  and  Pacific 
oceans,  flowing  from  the  equator  to  the  arc- 
tic regions,  while  the  cooler  and  heavier  cur- 
rents from  the  Arctic  have  swept  the  floor  of 
both  oceans  from  shore  to  shore  to  the  south- 


32  Where  did  Life  Begin? 

ward,  carrying  all  kinds  of  marine  life  from 
the  pole  toward  the  equator  with  them. 

It  may  be  well  in  this  connection  to  allude 
to  another  fact  seriously  affecting  the  bottom 
currents  from  the  pole  toward  the  equator 
of  both  air  and  ocean.  By  reason  of  the  re- 
volution of  the  earth  upon  its  axis,  a  given 
point  upon  its  surface  1,000  miles  south  of  the 
north  pole  moves  to  the  eastward  at  the  rate 
of  about  260  miles  an  hour,  while  another 
point  in  the  same  meridian  at  the  equator 
would  be  moving  to  the  eastward  a  little  more 
than  1,000  miles  an  hour;  so  every  cubic 
yard  of  air  and  water  which  starts  in  a  bottom 
current  from  the  polar  regions  for  the  equator 
must,  before  reaching  the  equator,  acquire  an 
eastward  motion  of  about  750  miles  an  hour. 
The  tendency,  therefore,  of  all  bottom  currents 
of  air  and  ocean  moving  to  the  south,  is  to 
press  to  the  westward  every  obstacle  met 
with  in  its  course,  and  the  result,  both  as  to  the 
currents  and  all  movable  things  they  come  in 
contact  with,  would  be  to  give  them  a  south- 
western course  and  movement. 

Now  it  is  a  strange  coincidence,  if  nothing 


Where  did  Life  Begin?  33 

more,  that  the  eastern  coasts  of  all  the  con- 
tinents have  a  southwestern  trend,  are  full 
of  bays,  inlets,  and  shoal  water,  as  though 
the  floor  of  the  ocean  was  being  constantly 
swept  up  against  them;  while  the  western 
coasts  are  more  abrupt,  straight,  and  touch 
deeper  water,  as  though  the  sweepings  from 
the  land  were  being  constantly  rolled  into 
the  sea  along  their  entire  lines. 

Notwithstanding  all  these  indications  of 
a  southern  or  southwestern  movement,  ever 
since  the  migration  of  plants  and  animals  first 
attracted  attention,  students  of  natural  science, 
careful  and  conscientious  observers,  able  and 
discriminating  investigators  have,  almost  with 
one  accord,  been  looking  east  and  west  across 
these  great  north  and  south  corrugations  and 
natural  barriers  for  the  paths  of  their  journey- 
ings,  searching  along  every  parallel  of  lati- 
tude, across  lofty  mountain  ranges,  broad  con- 
tinents, deep  and  wide  oceans,  and  ocean 
currents,  to  and  fro,  and  if  perchance  they 
looked  north  or  south  it  was  only  in  search 
of  some  ferry  or  ford  south  of  the  ice-fields 
by  which  to  pass  the  flora  and  fauna  from  one 
3 


34  Where  did  Life  Begin  ? 

continent  to  another,  and  thus  account  for 
what  is  very  evident,  viz. :  That  many  widely 
distributed  species  and  varieties  have  come 
from  the  same  locality  and  had  a  common 
ancestry  and  origin.  Is  it  not  evident  that 
the  very  plants  and  animals  (in  a  tribal  sense) 
whose  migrations  they  have  been  engaged  in 
unravelling,  were  as  much  older  than  ice  and 
snow  on  the  earth  as  it  would  require  in  time 
to  lower  the  average  temperature  over  a  vast 
area  from  a  tropical  to  a  frigid  climate  ? 

To  give  some  idea  of  this  immense  lapse 
of  time  as  before  intimated,  it  may  be  stated 
that  as  crystallized  rock  is  a  much  poorer  con- 
ductor of  heat  than  molten  rock,  so  when  the 
polar  and  temperate  zones  became  once  fairly 
encrusted,  the  main  escape  of  heat  from  the 
earth  would  forever  thereafter  have  been 
through  the  still  hotter  equatorial  belt  which 
was  surely  then  receiving,  as  now,  the  in- 
tensest  heat  of  the  sun  ;  and  so  it  must  have 
remained,  other  things  being  equal,  for  an 
immense  and  incalculable  period  of  time  be- 
fore its  complete  encrustation  ;  and  even  there- 
after its  over-heated  currents  of  air  and  water 


Where  did  Life  Begin?  35 

would   have   given   to   the   polar   regions    a 
torrid  climate  for  a  vast  period  of  time. 


V. 

LET  us  now  allude  briefly  to  a  few  facts  and 
circumstances  touching  the  existing  flora  and 
fauna  of  the  northern  hemisphere,  their  past 
remains  and  present  habitat,  which  are  en- 
tirely consistent  with  the  views  here  taken, 
and  equally  inconsistent  with,  and  contradic- 
tory of,  any  other  cause  of  dispersion  or  course 
of  migration  and  distribution  over  the  surface 
of  the  earth. 

The  evidences  of  former  tropical  life,  both 
vegetal  and  animal,  throughout  the  temper- 
ate zone  and  within  the  borders  at  least  of 
the  arctic  zone,  are  numerous  and  indisputa- 
ble. It  is  sufficient  to  mention  the  remains, 
found  far  within  the  regions  of  perpetual  ice 
and  snow,  of  the  hairy  elephant,  rhinoceros, 
and  mammoth,  of  the  plane-tree,  the  palm, 
and  the  magnolia.  It  is  true  that  the  ele- 
phantine remains  are  claimed  to  be  post- 
tertiary,  and  they  probably  are ;  but  does  it 


36  Where  did  Life  Begin? 

follow  that  either  they  or  their  ancestry  aban- 
doned a  tropical  climate  elsewhere  to  invade 
the  ice  and  snow  in  which  they  perished  ?  It 
is  much  more  probable  that  an  unfavorable 
climate,  increasing  in  its  severity  as  the  glacial 
period  came  on,  exterminated  them  where 
their  remains  are  found. 

Elaborate  theories  have  been  contrived  to 
account  for  their  having  been  carried  and  de- 
posited there,  and  other  theories  shifting  the 
earth's  axis  this  way  and  that ;  also  asserting 
elevations,  subsidences,  and  ocean  currents 
unlike  the  present  to  furnish  for  them  at  one 
time  or  another  a  suitable  habitat.  If  in  the 
process  of  the  earth's  cooling,  the  polar  lands 
and  seas  must  have  been  for  ages  as  hot  as 
they  could  be  and  maintain  tropical  or  any 
other  life,  it  seems  superfluous,  to  say  the  least 
(in  our  own  time  and  upon  the  discovery  of  the 
remains  of  such  life),  to  suppose  subsidences 
and  elevations  to  divert  and  extend  immense 
warm  ocean  currents  solely  to  provide  for 
that,  in  later  and  colder  periods,  which  was 
quite  well  enough  provided  for  long  before 
and  in  the  natural  order  of  things. 


Where  did  Life  Begin?  37 

But  it  is  a  conspicuous  fact  that,  whatever 
the  agency  evoked  to  keep  the  arctics  warm,  it 
has  in  each  instance  been  assumed  as  a  con- 
dition in  order  to  account  for  a  phenomenon, 
while  the  phenomenon  itself  has  rested  on  the 
condition  assumed.  And  neither  the  condition 
nor  the  phenomenon  have  at  any  time  been 
necessary  to  account  for  anything  if  this  globe 
has  really  passed  through  all  the  grades  of 
lowering  temperature  from  a  heated  mass  to 
its  present  condition.  It  is  perfectly  reason- 
able, therefore,  to  suppose  that  these  tropical 
forms  lived  when  the  arctic  climate  first  be- 
came suitable  for  them  and  died  where  their 
remains  are  found ;  especially  as  nothing  has 
yet  been  discovered  inconsistent  therewith 
and  so  much  corroborative  evidence  points  to 
the  same  conclusion. 

It  is  a  well-established  fact  that  the  Siberian 
elephants  had  an  extremely  long  and  heavy 
coat  of  hair,  with  an  undergrowth  of  close, 
warm  wool  as  a  covering.  It  is  scarcely  less 
certain  that  they  continued  in  the  Arctics  un- 
til the  commencement  of  the  first  glacial  pe- 
riod— the  beginning  of  the  quaternary — or  the 


38  Where  did  Life  Begin  ?  A 

age  of  man,  and  were  then  exterminated  by 
cold.  Can  it  be  true  that  the  ancestors  of 
these  hairy  elephants  migrated  to  the  Arctics  ? 
If  so,  they  came  from  a  warmer  climate,  for 
all  other  climates  are  and  always  have  been 
warmer,  and  they  must  have  come  from  a 
hairless  ancestry,  for  all  other  elephants  are 
hairless,  and  so  they  must  have  come  naked. 
They  must  also  have  come  from  lands  where 
their  food  was  better  and  more  abundant  than 
in  the  Arctics,  for  it  could  not  have  been 
poorer  or  scantier  anywhere  after  lands  south 
of  the  Arctics  were  habitable  for  elephants. 
Do  animals  having  no  enemies,  or  at  any  rate 
no  unconquerable  superiors,  migrate  from  lands 
of  plenty,  where  the  climate  is  such  that  they 
need  no  covering,  to  districts  where  food  is 
scarce  and  clothing  a  necessity  ?  It  is  more 
reasonable,  and  it  accords  better  with  the  law 
of  life,  to  suppose  that  the  elephants  of  the 
North  remained  in  the  ancient  home  of  all 
elephants,  and  came  to  have  hair  and  wool  in 
their  long  struggle  with  a  lowering  tempera- 
ture, while  those  that  moved  southward  with 
the  southward-moving  isothermal^  lines  have 


Where  did  Life  Begin?  39 

no  hair  because  their  ancestors  were  hairless 
and  they  have  needed  none.  If  the  hairy 
elephant  and  also  animals  now  tropical  have 
by  their  remains  hinted  and  suggested  that 
the  Arctic  regions  once  had  not  only  a  warm 
climate,  but  actually  teemed  with  tropical  life, 
the  remains  of  vegetal  life  have  positively  tes- 
tified to  it. 

"  As  the  tree  falls,  so  it  lies."  The  recently 
discovered  coal-beds  of  the  Arctics  prove  that 
the  coal-plants  once  flourished  there  in  abun- 
dance, and  where  the  coal-plants  flourished 
there  were  the  warm  climatic  conditions  of 
the  coal-plants  also.  Moreover,  the  fossils  of 
these  coal-beds;  and  many  of  the  species  of 
plants  of  which  they  were  composed,  are  iden- 
tical with  those  of  the  coal-beds  of  Europe 
and  America,  showing  not  only  a  like  tem- 
perature for  all,  but  a  kinship  and  common 
ancestry. 

These  same  plants,  such  as  tree  ferns  and 
lycopods,  dwarfed  and  stunted  by  the  cold  of 
our  present  tropics,  where  only  they  are  now 
found,  and  growing  to  the  height  of  but  a  few 
feet,  not  exceeding  a  man's  stature,  once  flour- 


40  Where  did  Life  Begin? 

ished  in  the  earlier  and  warmer  climates  of 
the  North,  growing  to  the  proportions  of 
forest  trees,  say  from  fifty  to  seventy-five  feet. 
Can  it  be  true  that  the  remains  of  these  plants 
found  in  the  coal-beds  of  the  Arctics  and  both 
continents  are  telling  us  that  the  whole  North- 
ern hemisphere  was  at  one  and  the  same  time 
blessed  with  a  uniform  climate  exactly  suited 
to  them  ?  Are  they  not  rather  testifying  that 
the  Arctic  climate  was  at  one  time  suitable 
for  them,  the  climate  of  the  Northern  temper- 
ate at  another  time,  and  at  a  later  period  still 
the  climate  of  the  torrid  zone,  in  the  warmer 
parts  of  which  their  stunted  forms  still  linger 
on  the  stage  ?  The  simple  fact  that  the  car- 
boniferous formation  through  these  living  rem- 
nants is  still  in  sight  in  the  tropics,  and  is 
buried  under  mountains  of  ice  and  snow  in  the 
Arctics,  is  to  my  mind  evidence  of  many  things, 
and  proof  positive  of  two :  first,  that  unless 
this  formation  is  ending  where  it  began,  which 
seems  almost  the  acme  of  absurdity,  then  it 
began  where  it  first  ended,  as  things  usually 
do,  and  that  locality  is,  beyond  dispute,  in  the 
Arctics  ;  second,  that  as  these  coal-plants  are 


Where  did  Life  Begin?  41 

only  found  now  in  the  tropics,  and  were  once 
living  in  the  Arctics,  it  follows  that  unless  they 
came  from  the  Arctics  originally  they  must 
have  travelled  over  and  receded  from  a  part  or 
all  of  the  distance  and  territory  between  the 
tropics  and  the  Arctics,  and  in  that  event  a 
warm  climate,  suitable  for  them,  must  have 
moved  northward  with  them,  or  at  the  time 
of  their  northward  movement  the  climate  of 
the  Arctics  must  have  been  warmer  than  the 
tropics  to  have  invited  them,  which  is  assum- 
ing one  useless  phenomenon  and  two  improba- 
bilities to  account  for  that  which  is  quite  easy 
of  solution  in  the  natural  order  of  things, 
and  without  recourse  to  either. 

In  all  cases  where  the  remains  of  identical 
forms  are  found  in  localities  thus  distant  from 
each  other,  one  of  two  conclusions  seems  in- 
evitable :  either  one  came  from  the  locality  of 
the  other,  or  they  both  had  a  common  ances- 
try located  in  some  other  place.  In  either 
case  the  species  must  have  travelled  as  far,  at 
least,  as  the  entire  distance  between  the  places 
where  their  remains  are  found ;  and  if  they 
had  a  common  ancestry  located  anywhere  ex- 


42  Where  did  Life  Begin? 

cept  on  a  straight  line  drawn  between  the 
two  places  where  their  remains  are  found,  the 
aggregate  distance  of  their  travels  must  have 
been  farther. 

Apply  this  principle  to  the  case  of  the  sev- 
eral remains  of  plants  of  the  same  species 
found  in  the  coal-beds  of  the  Arctics  and 
those  of  Pennsylvania,  and  it  follows,  first, 
that  the  whole  distance  between  these  widely 
separated  coal-beds,  at  the  least  calculation, 
has  in  a  tribal  sense  been  travelled  by  as 
many  species ;  second,  that  if  the  Pennsyl- 
vania plants  did  not  come  from  the  Arctics, 
then  Arctic  plants  must  have  come  from  Penn- 
sylvania, or  some  other  locality  warmer  than 
the  Arctics  (for  all  other  localities  except  the 
Antarctics  are  and  always  have  been  warmer), 
to  inhabit  a  territory  the  climate  of  which  was 
at  a  previous  period  precisely  adapted  to  them, 
but  at  the  time  of  their  coming  was  far  too 
cold,  unless  the  locality  they  came  from  was 
as  much  too  warm,  or  unless  the  earth  was 
formerly  heated  in  a  method  or  from  sources 
so  radically  different  from  the  present  that  the 
polar  regions  and  equatorial  belt  had  the  same 


Where* did  Life  Begin?  43 

climate.  To  state  such  suppositions  in  full 
furnishes  for  them  the  best  possible  refutation. 
The  most  reasonable  conclusion  to  be 
drawn  from  these  facts  are  that  the  plants 
whose  remains  are  found  in  the  Arctic  coal- 
beds  lived  there  when  the  climate  of  the 
Arctics  was  suitable  for  them,  and  as  there 
are  no  obstacles  nor  inconsistencies  to  a  south- 
ward movement,  and  never  have  been,  that 
all  the  like  species  found  in  the  European  and 
American  coal-beds  came  generically  from  the 
same  Northern  locality  and  ancestry.  But  as 
the  Arctics  are  now  too  cold  for  these  plants, 
and  the  tropics  are  not,  it  would  seem  about 
as  sound  as  the  average  geological  conclu- 
sion that  their  appropriate  climate  came 
southward  with  them,  or  rather  that  they 
came  with  it.  But,  again,  what  is  true  of  the 
course  of  these  plants  must  have  been  true 
of  all  plants  living  under  the  same  conditions, 
and  as  animals  always  move  with  and  follow 
their  food,  so  it  is  as  certain  that  all  the  flora 
and  fauna  of  the  Northern  hemisphere  made 
a  vast  Southern  movement  from  the  Arctics 
over  the  Eastern  and  Western  continents 


44  Where  did  Life  Begin  ? 

during  the  age  of  the  movement  of  these  coal- 
plants,  as  it  is  that  the  coal-plants  made  it 
themselves.  And  what  is  true  of  the  course 
of  migration  of  plants  and  animals  of  their 
age  would,  under  uniform  laws,  causes,  and 
conditions,  be  true  of  such  movements  in  all 
ages. 


VI. 


A  GREAT  variety  of  opinions  have  been  en- 
tertained and  many  interesting  theories  formed 
in  accounting  for  the  similarity  of  species  and 
genera  upon  the  Eastern  and  Western  con- 
tinents. If,  as  we  have  claimed,  a  zone  around 
the  North  Pole,  sufficiently  removed  therefrom 
to  receive  the  minimum  of  the  sun's  influence 
consistent  with  animal  and  vegetal  life,  has 
necessarily,  in  its  climatic  progress,  been  in 
condition  to  maintain  successively  all  forms  of 
life  which  have  ever  existed  on  the  earth,  and 
if  a  region  of  increasing  cold  surrounded  by 
this  zone  dispersed  these  various  forms  of 
life  in  all  directions  down  the  Asiatic,  the 
European,  and  North  American  continents 


Where  did  Life  Begin  ?  45 

toward  the  equator — if  this  hypothesis  is  in- 
deed true,  and  if  all  this  occurred,  we  should 
naturally  expect  to  find  a  marked  resemblance 
in  much  of  the  flora  and  fauna,  throughout  all 
the  continents,  of  the  northern  hemisphere. 
And  this  is  precisely  what  we  do  find. 

It  requires  but  little  scientific  training  to  con- 
clude that  the  mammoth,  mastodon,  elephant, 
buffalo,  bison,  elk,  deer,  hare  and  sheep,  the 
wolf,  fox,  weasel  and  martin,  the  beaver,  otter, 
bear,  tiger,  panther,  lion,  mountain  lion  and 
wild  cat,  the  crocodile,  alligator,  frog,  salmon, 
bass,  trout  and  many  other  fresh-water  fish  ; 
that  the  butterflies,  bees,  locusts,  and  numer- 
ous kinds  of  ants  and  beetles  ;  that  the  end- 
less tribes  of  small  land  birds  ;  that  the  oak, 
elm,  maple,  ash,  birch,  beech,  larch,  chestnut, 
and  many  pines,  together  with  flowering 
plants,  mosses,  grasses,  ferns  and  shrubs  in- 
numerable, which  inhabit  or  have  inhabited 
all  the  continents  of  the  northern  hemisphere 
almost  indiscriminately,  are  related  to  each 
other,  and  had  respectively  some  common 
ancestry  and  origin. 

Neither   the   indigenous    theory   nor    any 


46  Where  did  Life  Begin  ? 

other  hypothesis,  for  that  matter,  can  or  will 
ever  account  for  a  likeness  so  much  more 
marked  between  certain  plants  and  animals 
of  the  eastern  and  western  continents  than 
in  the  similarity  of  their  surroundings,  and 
the  antecedent  conditions  of  their  habitat. 

This  marked  similarity  of  the  forms  of  life 
in  widely  separated  and  dissimilar  environment 
is  however  possible,  and  only  possible,  in 
case  they  once  migrated  from  the  same  lo- 
cality, and  it  is  abundantly  safe  to  add  that,  if 
there  is  any  one  locality  from  which  they  all 
could  have  migrated  except  a  northern  zone, 
as  herein  described,  it  is  yet  to  be  discov- 
ered. Under  the  most  plausible  supposition 
of  any  other  one  locality,  they  certainly  would 
have  had  to  pass  through  some  part  of  this 
northern  zone  to  have  reached  their  pres- 
ent destination.  This  hypothesis,  of  both  a 
north  and  south  movement  in  order  to  pass 
from  continent  to  continent  presents  to  my 
mind  this  dilemma.  To  suppose  that  plants 
and  animals  took  such  long  and  circuitous 
routes  for  the  defined  purpose  of  reaching 
new  fields  and  continents,  is  to  endow  them 


Where  did  Life  Begin?  47 

with  the  forethought  and  intelligence  of  a 
Columbus,  while  to  claim  that  they  were 
coaxed  and  led  along  by  favoring  conditions 
is  to  assert  that  all  the  conditions  of  this  long 
northern  journey  to  find  a  suitable  crossing, 
and  afterward  of  an  equally  long  southern  trip 
to  their  present  homes,  must  have  been,  if 
there  has  been  any  sort  of  uniformity  in  the 
thermal  system  of  the  earth  of  an  opposite 
character,  and  therefore,  if  in  one  case  they 
were  favorable  to  the  movement,  in  the  other 
they  must  have  been  equally  unfavorable  ;  but 
plants  never  move,  and  animals  rarely,  against 
conditions  which  are  unfavorable  to  any  ex- 
tent. 

It  is  true,  so  far  as  simple  direction  is  con- 
cerned, that  in  the  exceptional  case  of  the 
receding  of  the  ice  at  the  close  of  the  glacial 
period,  plants  and  animals  which  had  been 
hurried  southward  by  the  cold  moved  again 
to  the  northward,  with  the  like  exceptional 
movement  of  a  warm  climate  to  the  north- 
ward. Both  exceptions  are,  however,  of  just 
such  a  character  as  to  prove  the  rule.  In 
each  case  the  whole  movement  of  organic  life 


48  Where  did  Life  Begin? 

in  the  northern  hemisphere  was  induced  by  a 
like  movement  of  isothermal  lines  and  cli- 
matic conditions,  and  while  in  one  instance  it 
was  from  the  south  to  the  north,  the  phenom- 
enon no  more  suggests,  when  considered  in 
connection  with  its  exceptional  and  anomalous 
causes,  that  the  general  movement  has  not 
been  in  the  opposite  direction,  than  the  fact 
that  tidal  waves  setting  up  for  hundreds  of 
miles  in  great  rivers  would  indicate  that  their 
main  currents  were  not  always  and  constantly 
to  the  sea. 

It  hardly  admits  of  two  opinions,  that  or- 
ganic life  has  in  the  main  either  moved  from 
the  polar  regions  to  the  tropics  or  vice  versa. 
For,  commencing  in  any  given  locality  between 
the  two,  and  it  could  not  have  moved  both 
ways;  the  temperature,  climate,  and  other 
conditions  north  and  south  of  every  locality 
are,  and  must  ever  have  been,  so  dissimilar 
that  if  they  favored  a  movement  in  one  direc- 
tion they  would  have  forbidden  it  in  the  other. 
Now  as  east  and  west  movements  are  im- 
possible, to  any  great  extent,  and  as  the  con- 
ditions favorable  to  one  form  of  life  are,  as  a 


Where  diet  Life  Begin?  49 

rule,  favorable  to  all,  it  follows  that  the  general 
movement  of  all  the  organic  life  of  the  earth 
is,  and  ever  has  been,  from  the  warmer  toward 
the  colder,  or  from  the  colder  toward  the 
warmer,  and  this  too  from  one  extreme  to 
the  other,  and  to  my  mind  the  movement  from 
the  colder  toward  the  warmer,  from  the  north 
to  the  south  in  our  hemisphere,  seems  not  only 
entirely  reasonable,  but  the  facts  sustaining 
\\.  positive,  and  the  conclusion  inevitable. 

It  is  a  well-recognized  fact  and  worthy  of 
notice  in  this  connection,  that  all  plants  and 
animals  moved  by  man  a  few  degrees  from 
the  north  to  the  south  in  our  hemisphere  are 
improved  and  become  more  highly  developed, 
vigorous  and  prolific  by  reason  of  the  transfer, 
while  a  like  movement  in  the  opposite  di- 
rection produces,  in  a  degree  proportioned  to 
the  distance  moved,  all  the  contrary  effects 
of  sterility  and  degeneration ;  so  that  this 
southern  movement,  in  addition  to  all  its  other 
probabilities,  is  consonant  with,  and  in  the 
direct  line  of,  the  highest  development  and 
evolution  of  both  plants  and  animals. 

In  the  light  of  this  fact  let  us  ask  what 
4 


50  Where  did  Life  Begin? 

changes  would  probably  have  taken  place  in 
those  animals  lingering  behind  in  the  arctic 
zone  after  the  species  to  which  they  belonged 
had  chiefly  moved  southward,  remaining  there 
until  its  tropical  climate  had  become  temper- 
ate and  then  frigid.  These  remnants,  in  their 
struggle  for  adaptation  to  the  new  conditions 
of  increasing  cold  would,  after  passing  through 
the  temperate  and  encountering  the  frigid 
climate,  doubtless  have  been  exterminated  or 
would  have  become  degenerations,  like  the 
whale,  the  walrus,  the  sea-lion,  and  the  whole 
seal  tribe  of  the  present  arctic  regions,  reced- 
ing slowly  toward  the  water  and  cold-blooded 
life  from  which  possibly  all  animal  life  origi- 
nally came. 

These  degenerations  themselves  furnish 
some  proof  that  the  arctic  regions  once  had 
a  warm  climate ;  to  hold  otherwise  is  to 
allege  that  their  ancestry  forsook  a  favorable 
climate  for  one  in  which  they  could  only  es- 
cape extermination  by  degenerating  and  tak- 
ing to  the  water  for  subsistence.  I  think  it 
more  reasonable  to  assume  that  the  favorable 
climate  forsook  them,  and  once  caught  in  un- 


Where  did  Life  Begin?  51 

favorable  conditions  they  have  been  going  on 
from  bad  to  worse  in  a  fierce  struggle  for 
existence. 

Evolution  and  degeneration  in  the  organic 
world  are,  in  one  phase  at  least,  the  result  of 
changes  in  the  counter  relations  of  demand 
and  supply.  Whenever  in  respect  to  the  or- 
ganism, and  all  things  possibly  useful  to  it, 
the  supply  by  the  smallest  degree  exceeds 
the  demand,  old  wants  and  capacities  are  en- 
larged, and  new  wants  creep  into  existence; 
therewith  old  organs  are  improved  and  new 
ones  developed  for  securing  and  appropriating 
by  defence,  contest,  and  competition,  this  sur- 
plus ;  the  organism  thus  acquires  varied  appe- 
tites, increased  activity,  diversified  employ- 
ments, keener  sensibilities,  and  a  wider  range 
of  life,  and  so  passes  by  such  changes  from 
the  simpler  to  the  more  complex  in  form 
and  function — and  this  is  evolution.  So,  on  the 
other  hand,  when  the  demand  is  greater  than 
any  available  supply,  the  wants  denied  must 
be  suppressed;  therewith  the  organs  and  ca- 
pacities specialized  for  their  gratification  first 
fall  into  disuse,  are  then  atrophied,  and  thus 


52  Where  did  Life  Begin? 

the  organism  with  restricted  activity,  limited 
employments,  and  a  narrower  range  of  life, 
recedes  from  the  complex  to  the  simpler  in 
form  and  function — and  this  is  called  degener- 
ation. It  is  all  the  result  of  the  changing  re- 
lations of  demand  to  supply.  And  in  the  very 
last  analysis,  in  every  case,  I  more  than  sus- 
pect that  all  life  which  occurs  within  a  certain 
range  of  heat  is  the  demand,  and  that  all  heat 
which  is  suitable  to  such  life-range  is  the 
supply. 

These  cases  of  degeneration  in  different  or- 
ders are  more  numerous  than  was  formally 
supposed.  They  have,  in  fact,  been  just  as 
frequent  as  the  permanent  success  of  a  species 
(by  limiting  their  needs)  in  their  struggle  for 
adaptation  to  an  adverse  environment,  one 
which  continually  diminished  the  variety  and 
quantity  of  supplies,  and  yet  changed  in  its 
unfavorable  conditions  so  slowly  as  not  to 
exterminate  the  species. 

This  fact  offers  us  another  suggestion  in 
this  connection,  If  it  is  true  that,  in  com- 
mon with  many  existing  plants  and  animals, 
the  ancestry  of  man — some  animal  with  a 


Where  did  Life  Begin?  53 

thumb,  and  so  having  the  possibility  of  all 
things — shared  this  northern  home,  this  com- 
mon and  immensely  remote  origin,  earlier  by 
long  epochs  than  the  glacial  period,  it  would 
afford  a  possible  ground  for  the  claim  of  the 
unity  of  the  origin  of  man,  and  also  a  reason 
for  the  absence  on  the  earth  of  his  immediate 
predecessor.  His  arboreal  progenitor  in  the 
pioneer  ranks  of  this  great  southern  move- 
ment, ages  before  the  quatenary  (during  all 
of  which  period  man  has  probably  inhabited 
the  earth),  was  possibly  driven  naked  by  the 
ever  following,  merciless  cold,  thus  keeping 
him  within  the  southward  moving  tropical  cli- 
mate, down  the  eastern  and  western  conti- 
nents alike,  until  it  and  he,  arriving  in  the 
lapse  of  ages  at  the  equatorial  belt,  and  being 
always  at  the  head  and  still  rising  in  the  scale 
of  being  by  this  movement,  discipline,  and 
process,  became  sufficiently  advanced  by  slow 
degrees  to  build  fires,  clothe  himself,  make 
implements,  and,  possibly,  domesticate  ani- 
mals, at  least  the  first  and  most  useful  to 
primitive  man,  the  dog,  and  so  prepared  for 
conflict  and  for  all  climates,  turned  backward 


54  Where  did  Life  Begin? 

to  the  verge  of  everlasting  ice,  subduing, 
slaying,  and  exterminating,  first  his  own  an- 
cestry, his  nearest  but  now  weak  rival,  which 
by  lingering  behind  and  struggling  for  life  in 
a  climate  of  increasing  cold,  would  have  be- 
come extremely  degenerated  and  so  easily 
disposed  of,  if  not  actually  exterminated,  by 
the  climate  itself,  thus  leaving  as  the  nearest 
in  resemblance  to  man,  and  yet  the  remotest 
in  actual  relationship  both  to  him  and  his  an- 
cestry, the  later  tribes  of  anthropoid  apes 
since  developed  nearer  to  the  equator,  from 
the  next  lower  animals  which  accompanied  him 
in  his  southward  march. 

This  last  proposition,  however,  is  but  a 
vague  and  very  deductive  supposition,  for 
which  nothing  is  claimed  beyond  a  possibility, 
or  bare  probability.  Notwithstanding,  to  sus- 
tain the  main  conclusion  herein  stated,  with  all 
the  essential  results  and  outcome  of  the  same, 
it  seems  to  me  to  be  only  necessary  to  claim, 
what  would  be  generally  admitted,  viz.  :  that 
the  whole  earth  was  at  one  time  too  warm  to 
maintain  life,  and  that  no  discovered  cause  or 
fact  points  to  a  less  average  difference  between 


Where  did  Life  Begin?  55 

the  temperature  of  the  tropics  and  the  polar 
zones  in  the  past  than  we  find  existing  between 
them  to-day.  For  even  such  a  condition  and 
difference  of  temperature  would  have  given 
to  the  polar  regions  first  a  tropical  climate 
and  life,  then  a  temperate  climate  and  life 
appropriate  to  it,  and  each  for  an  immense 
epoch  before  the  equatorial  belt  would  have 
been  habitable  for  any  known  prganism. 


VII. 

ONE  glance  at  the  immediate  cause — the 
proximate  moving  power — of  all  this  vast,  va- 
ried, and  complex  machinery  and  movement 
of  life,  and  I  have  done.  We  have  been  thus 
far  contemplating  and  discussing  the  results 
of  this  power  ;  attempting  a  partial  description 
of  the  methods  made  manifest  in  its  grand  life- 
bearing  and  eliminating  work ;  discovering  its 
ways  in  prompting,  developing,  sifting,  and 
destroying  life  ;  following  in  the  paths  and  ex- 
amining the  effects  of  its  great  zones  or  belts 
of  graded  climates  girding  the  earth,  and  which 


56  Where  did  Life  Begin? 

have  swept  from  the  poles  to  the  equator — one 
after  the  other,  and  age  after  age,  through  a 
period  so  vast,  so  incomprehensible,  that  even 
the  epochs  of  which  it  is  composed  seem  to 
us  almost  like  so  many  eternities.  Let  us 
draw  near,  observe  and  define  more  closely 
this  wonderful  force,  an  excess  of  which  for- 
bids life,  a  deficiency  of  which  destroys  life, 
and  without  wjiich  life  is  impossible. 

Heat  is  the  proximate  cause  of  all  activity. 
With  it  life  comes  and  goes.  The  departure 
of  heat  which  we  call  "  cold  "  is  death.  Cold 
huddles  and  quiets  the  molecules  of  all  known 
substances.  Life  cannot  invade  its  precincts. 
As  cold  dispersed  the  plants  and  animals 
from  the  polar  regions,  so  it  has  set  up  an 
impassable  barrier  against  their  return.  Every 
high  mountain  has  a  cold  line  above  which 
nothing  thrives.  The  earth  is  growing  colder 
age  by  age.  Our  next  neighbor,  the  moon, 
has  already  become  cold  and  lifeless,  while 
yet  receiving  its  full  proportion  of  sun-heat. 
Certain  grades  or  degrees  of  heat  then  not 
only  constitute  the  moving  power  of  all  life, 
but  does  it  not  seem  probable  that  the  con- 


Where  did  Life  Begin?  57 

stant  lowering  temperature  of  the  earth,  the 
constant  loss  of  heat  during  its  life-history, 
with  the  concurrent  effects  thereof,  has  been 
directly  or  indirectly  the  great  and  all-suffi- 
cient exterminator  of  extinct  species  ? 

Of  course  heat  and  cold  are  comparative 
terms.  But  notwithstanding,  as  the  whole 
globe  was  once  too  hot,  and  certain  portions 
of  it  are  now  too  cold  for  life,  it  follows  con- 
clusively that  there  is  a  definite  range  of 
temperature,  a  fixed  number  of  degrees  of 
heat,  which  constitutes  the  gamut  of  life.  No 
organism  known  can  exist  an  instant  above 
or  below  it.  The  numerous  subdivisions  of 
this  life-scale,  both  cause  and  define  the  con- 
ditions most  favorable  to  the  development  of 
the  several  species  and  varieties  of  plants  and 
animals.  But  a  portion  of  these  subdivisions, 
viz. :  the  higher  heat  lines  of  this  great  life- 
range  have  passed  from  the  earth  forever,  or 
rather,  the  earth  has  passed  through  them, 
dropping  from  time  to  time  the  extinct  species 
which  were  only  fitted  for  hotter  climates, 
while  the  cooler  subdivisions,  the  lower  heat 
lines  within  this  gamut  of  life,  we  are  now 


58  Where  did  Life  Begin? 

passing  through,  and  they  now  constitute,  as 
their  predecessors  once  did,  the  great  zones 
of  temperature — the  isothermal  lines  encir- 
cling the  globe  and  moving  forever  slowly 
from  the  poles  to  the  equator,  each  bearing 
with  it,  developing,  and  raising  in  the  scale  of 
being  its  peculiar  forms  of  life. 

Earth's  wrinkled  crust  reveals  to  us  the 
beginnings  of  life,  and  our  own  age  gives 
plain  indications  of  its  ending.  The  lauren- 
tian  rocks  stood  god-father  to  the  first-born, 
and  to-day  the  death-line  encircling  the  poles, 
drawn  where  life  first  began,  studded  with 
white  pinnacled  monuments,  guards  from  in- 
trusion the  cemetery  of  departed  ages.  The 
last  life  on  earth  may  be  as  remote  in  the 
dim  future  as  the  first  is  in  the  shadowy  past, 
but  the  indications  are  that  within  the  polar 
regions  we  have  now  the  beginning  of  the 
end. 

Thus  the  arctic  zone,  which  was  earliest 
in  cooling  down  to  the  first  and  highest  heat 
degree  in  the  great  life-gamut,  was  also  first 
to  become  fertile,  first  to  bear  life,  and  first 
to  send  forth  her  progeny  over  the  earth.  So 


Where  did  Life  Begin  ?  59 

too,  in  obedience  to  the  universal  order  of 
things,  she  was  first  to  reach  maturity,  first  to 
pass  all  the  subdivisions  of  life-bearing  clim- 
ate, and  finally  the  lowest  heat  degree  in  the 
great  life-range,  and  so  the  first  to  reach 
sterility,  old  age,  degeneration,  and  death. 
And  now  cold  and  lifeless, — wrapped  in  her 
snowy  winding  sheet,  the  once  fair  mother  of 
us  all,  rests  in  the  frozen  embrace  of  an  ice- 
bound and  everlasting  sepulchre. 


APPENDIX. 


"  In  scientific  investigations  it  is  permitted  to  in- 
vent any  hypothesis,  and  if  it  explains  various  large 
and  independent  classes  of  facts,  it  rises  to  the  rank 
of  a  well-grounded  theory." — CHARLES  DARWIN  :  Ani- 
mals and  Plants  under  Domestication,  vol.  i.,  page  9. 

"The  globe,  when  its  continental  area  had  become 
in  the  main  terra  firma,  may  hence  have  had  other 
great  areas  unsolidified." — DANA'S  Manual  of  Geology. 

"  That  tendency  which  we  see  in  the  human  races, 
to  overrun  and  occupy  each  other's  lands  as  well  as 
the  lands  inhabited  by  inferior  creatures,  is  a  tendency 
exhibited  by  all  classes  of  organisms,  in  all  varieties 
of  ways." — HERBERT  SPENCER  :  Principles  of  Biology, 
vol.  vii.,  page  315. 

"  Any  alteration  in  the  temperature  of  a  climate  or 
its  degree  of  humidity,  is  unlikely  to  affect  simulta- 
neously the  whole  area  occupied  by  a  species ;  and 
further,  it  can  scarcely  fail  to  happen  that  the  addition 
or  subtraction  of  heat  or  moisture  will  give  to  a  part 


62  Appendix. 

of  some  adjacent  area  a  climate  like  to  that  to  which 
the  species  has  been  habituated." — HERBERT  SPENCER: 
Principles  of  Biology,  vol.  i.,  page  428. 

"  Since  in  other  periods  we  know  that  life  was  al- 
ways present  when  its  conditions  were  present,  it  is 
not  unreasonable  to  look  for  the  first  traces  of  life 
in  this  formation  (the  lower  Laurentian),  in  which 
we  find  for  the  first  time  the  completion  of  those 
arrangements  which  make  life,  in  such  forms  of  it  as 
exist  on  our  planet,  possible." — DR.  J.  W.  DAWSON  : 
Retiring  address  as  President  of  the  American  Associa- 
tion for  the  Advancement  of  Science,  1883. 

"As  so  many  animals  are  dependent  on  vegetation, 
its  changes  immediately  affect  their  distribution." — 
ALFRED  RUSSEL  WALLACE  :  Distribution  of  Animals, 
vol.  i.,  page  43. 

"  There  are  few,  I  presume,  who  reflect  on  the  sub- 
ject that  will  not  readily  admit  that,  whether  as  regards 
the  great  physical  changes  which  are  taking  place  on 
the  surface  of  the  globe,  or  as  regards  the  growth  and 
distribution  of  plant  and  animal  life,  the  ordinary  cli- 
matic agents  are  the  real  agents  at  work,  and  that 
compared  with  them  all  other  agencies  sink  into  in- 
significance."— CROLL'S  Climate  and  Time. 

"  Even  in  the  arctic  zone  there  were  in  the  miocene 
great  forests  of  beach,  oak,  poplar,  walnut,  and  red- 


Appendix.  63 

wood,  with  magnolias,  alders,  and  others." — JAMES  D. 
DANA,  LL.D.  :  The  Geological  Story  briefly  Told,  page 
200. 

"  At  the  same  time  (the  miocene),  or  perhaps  some- 
what earlier,  a  temperate  climate  extended  into  the 
arctic  regions,  and  allowed  a  magnificent  vegetation 
of  shrubs  and  forest  trees,  some  of  them  evergreen, 
to  flourish  within  twelve  degrees  of  the  Pole." — AL- 
FRED RUSSEL  WALLACE  :  Distribution  of  Animals,  vol.  i., 
page  41. 

"Coal-beds  of  carboniferous  age  are  extensively 
developed  in  the  arctic  regions." — JAMES  CROLL  :  Cli- 
mate and  Time,  page  198. 

"  The  woolly  rhinoceros,  on  the  other  hand,  may  be 
viewed  as  a  northern  form,  since  it  is  met  with  in 
vast  abundance  in  the  arctic  regions  of  Siberia  as  well 
as  in  Europe,  and  has  not  been  found  south  of  the 
Alps  and  Pyrenees." — W.  BOYD  DAWKINS,  M.A., 
F.R.S.,  F.G.S.  :  Cave  Hunting,  page  400. 

"  That  an  equable  condition  of  climate  extended 
to  near  the  North  Pole  is  proved  by  the  fact  that  in 
the  arctic  regions  vast  masses  of  carboniferous  lime- 
stone, having  all  the  character  of  the  mountain  lime- 
stone of  England,  have  been  found." — JAMES  CROLL  : 
Climate  and  Time,  page  297. 


64  Appendix. 

u  This  writing  and  these  figures  consist  of  the  re- 
mains of  animals  and  plants  which,  in  the  great  ma- 
jority of  cases,  have  lived  and  died  in  the  very  spot 
in  which  we  now  find  them,  or  at  least  in  the  imme- 
diate vicinity." — T.  H.  HUXLEY  :  Origin  of  Species, 
page  42. 

"  It  follows  .  .  .  that  man,  issuing  from  a 
1  mother-region  '  still  undetermined,  but  which  a  num- 
ber of  considerations  indicate  to  have  been  in  the 
north,  has  radiated  in  several  directions  ;  that  his  mi- 
grations have  been  constantly  from  north  to  south." 
— M.  LE  MARQUIS  G.  DE  SAPORTA  :  Popular  Science 
Monthly,  October,  1883,  page  753. 


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